The overall objective of this project is to examine certain principles of organization among populations of neurons and to devise means of recording the activity of populations of neurons. One such principle is that the independent components of the pattern of activity of a population of similar neurons are related to the physiological function of those neurons. Thus, among neurons of sensory systems, the strength of the connections from the afferents onto neurons at a given level would tend to be such that these neurons detect the independent component patterns among these afferent fibers. In motor systems, the independent components in the activity of a population of neurons would be an estimate of the degrees of freedom in the motor command signals and/or sensory information feeding onto them.